import gradio as gr
from typing import Any, Dict, List
from plotly.graph_objs import Figure, Scatter
import pandas as pd
import datetime as dt
import numpy as np
import pandas as pd
from common import get_db
import plotly.express as px

MAX_CHARTS_IN_PAGE = 40
NUM_COLS = 4


def coerce_to_number(val):
    """Try converting to int/float, else return original string."""
    if val is None:
        return None
    try:
        # First try integer
        i = int(val)
        return i
    except (ValueError, TypeError):
        try:
            # Then try float
            f = float(val)
            return f
        except (ValueError, TypeError):
            return val  # fallback to original (string, unit, etc.)


def build_trend_figure(trend_doc: Dict[str, Any]) -> Figure:
    """Make a Plotly line chart for a single test's trend_data with optional reference ranges."""
    points = trend_doc.get("trend_data", [])
    ref = trend_doc.get("test_reference_range") or {}  # safe default {}

    if not points:
        fig = Figure()
        fig.update_layout(
            title="No trend data", xaxis_title="Date", yaxis_title="Value"
        )
        return fig

    # Parse dates and values
    date_value_pairs = []
    for p in points:
        date = pd.to_datetime(p.get("date"), errors="coerce")
        value = coerce_to_number(p.get("value"))
        if pd.notna(date) and value is not None:
            date_value_pairs.append((date, value))

    # Sort by date
    date_value_pairs.sort(key=lambda x: x[0])
    dates, values = zip(*date_value_pairs) if date_value_pairs else ([], [])

    fig = Figure()

    # === Reference Range Logic (only if present) ===
    ref_min = coerce_to_number(ref.get("min")) if ref else None
    ref_max = coerce_to_number(ref.get("max")) if ref else None

    if ref_min is not None and ref_max is not None:
        fig.add_shape(
            type="rect",
            x0=min(dates),
            x1=max(dates),
            y0=ref_min,
            y1=ref_max,
            fillcolor="rgba(0,200,0,0.1)",  # light green
            line=dict(width=0),
            layer="below",
        )
    elif ref_min is not None:
        fig.add_trace(
            Scatter(
                x=[min(dates), max(dates)],
                y=[ref_min, ref_min],
                mode="lines",
                name="Min Ref",
                line=dict(color="green", dash="dot"),
            )
        )
    elif ref_max is not None:
        fig.add_trace(
            Scatter(
                x=[min(dates), max(dates)],
                y=[ref_max, ref_max],
                mode="lines",
                name="Max Ref",
                line=dict(color="red", dash="dot"),
            )
        )

    # === Actual Trend Data ===
    fig.add_trace(
        Scatter(
            x=dates,
            y=values,
            mode="lines+markers",
            name=trend_doc.get("test_name", "Trend"),
        )
    )

    fig.update_layout(
        margin=dict(l=30, r=20, t=40, b=30),
        xaxis_title="Date",
        yaxis_title="Value",
        title=f"{trend_doc.get('test_name','')}",
    )
    fig.update_yaxes(autorange=True)
    fig.update_xaxes(
        autorange=True, tickformat="%Y-%m-%d", tickangle=-45, tickmode="auto"
    )
    return sanitize_plotly_figure(fig)


async def load_all_trend_figures(patient_id: str):
    """Fetch all test trend docs and return list of Plot figures."""
    if not patient_id:
        return []
    db = get_db()
    cursor = db.trends.find({"patient_id": __import__("bson").ObjectId(patient_id)})
    docs = await cursor.to_list(length=None)
    figures = [build_trend_figure(doc) for doc in docs if doc]
    return figures


async def update_trends(patient_id, page=0, num_cols=NUM_COLS):
    figures = await load_all_trend_figures(patient_id)
    total_pages = (len(figures) - 1) // MAX_CHARTS_IN_PAGE + 1

    start = page * MAX_CHARTS_IN_PAGE
    end = start + MAX_CHARTS_IN_PAGE
    page_figures = figures[start:end]

    outputs = []
    for i in range(MAX_CHARTS_IN_PAGE):
        if i < len(page_figures):
            title = page_figures[i].layout.title.text
            page_figures[i].update_layout(title="")
            outputs.append(gr.update(value=page_figures[i], visible=True, label=title))
        else:
            outputs.append(gr.update(visible=False, value=None, label=""))

    # Enable/disable buttons
    prev_disabled = page == 0
    next_disabled = page >= total_pages - 1

    # return as separate outputs + page + page info
    return (
        *outputs,  # plots
        page,  # page number
        f"Page {page+1} / {total_pages}",  # page info
        gr.update(interactive=not prev_disabled),  # Prev button
        gr.update(interactive=not next_disabled),
    )  # Next button


async def reset_trends():
    """
    Clears all trend plots and resets page info.
    Returns a list of gr.update(...) objects matching the outputs of update_trends.
    """
    outputs = []
    for _ in range(MAX_CHARTS_IN_PAGE):
        outputs.append(gr.update(visible=False, value=None, label=""))

    # Reset page number and page info
    page = 0
    page_info = "Page 0 / 0"

    return (
        *outputs,
        page,
        page_info,
        gr.update(interactive=False),
        gr.update(interactive=False),
    )


def reset_vitals_plots():
    """
    Clears all vitals plots and resets page info.
    Returns a list of gr.update(...) objects matching the outputs of update_trends.
    """
    outputs = []
    for _ in range(20):
        outputs.append(gr.update(visible=False, value=None, label=""))

    return (*outputs,)

def reset_latest_vitals_labels():
    """
    Clears all latest vitals labels and resets page info.
    Returns a list of gr.update(...) objects matching the outputs of update_trends.
    """
    outputs = []
    for _ in range(20):
        outputs.append(gr.update(visible=False, value=None, label=""))

    return (*outputs,)


def _to_jsonable_dt(x):
    if isinstance(x, pd.Timestamp):
        return x.to_pydatetime()  # or x.isoformat()
    if isinstance(x, np.datetime64):
        return pd.to_datetime(x).to_pydatetime()
    return x


def sanitize_plotly_figure(fig):
    # traces (x/xbins/…)
    for tr in fig.data:
        if hasattr(tr, "x") and tr.x is not None:
            try:
                tr.x = [_to_jsonable_dt(v) for v in tr.x]
            except TypeError:
                # x may be a scalar
                tr.x = _to_jsonable_dt(tr.x)

    # shapes (x0/x1)
    if fig.layout.shapes:
        for s in list(fig.layout.shapes):
            if getattr(s, "x0", None) is not None:
                s.x0 = _to_jsonable_dt(s.x0)
            if getattr(s, "x1", None) is not None:
                s.x1 = _to_jsonable_dt(s.x1)

    # annotations (x)
    if fig.layout.annotations:
        for a in list(fig.layout.annotations):
            if getattr(a, "x", None) is not None:
                a.x = _to_jsonable_dt(a.x)

    # axes ranges (range can contain datetimes)
    if getattr(fig.layout, "xaxis", None) and getattr(fig.layout.xaxis, "range", None):
        fig.layout.xaxis.range = [_to_jsonable_dt(v) for v in fig.layout.xaxis.range]

    return fig


def next_page(page, figures_len):
    total_pages = (figures_len - 1) // MAX_CHARTS_IN_PAGE + 1
    return min(page + 1, total_pages - 1)


def prev_page(page):
    return max(page - 1, 0)


async def render_vitals_plot_layout(patient_id):
    docs = await get_db().get_vitals_trends_by_patient(patient_id)
    figures = [build_trend_figure(doc) for doc in docs if doc]
    # Pad/truncate to exactly 20 charts
    if len(figures) > 20:
        figures = figures[:20]
    elif len(figures) < 20:
        while len(figures) < 20:
            empty_fig = Figure()
            empty_fig.update_layout(
                title="No Data",
                xaxis=dict(visible=False),
                yaxis=dict(visible=False),
                margin=dict(l=30, r=20, t=40, b=30),
            )
            figures.append(empty_fig)

    plots = []
    for fig in figures:
        plots.append(gr.Plot(value=fig, label=fig.layout.title.text))
        fig.update_layout(title=None)
    return plots